Compounds which have retinoid-like biological activity are well known in the art and are described in numerous United States patents including, but not limited to, U.S. Pat. Nos. 5,466,861; 5,675,033 and 5,917,082, all of which are herein incorporated by reference. Preclinical studies with rexinoids suggest that selective activation of retinoid X receptors (RXR), which modulate functions associated with differentiation, inhibition of cell growth, apoptosis and metastasis, may be useful in treating a variety of diseases associated with the biochemical functions modulated by RXR.
For example, Targretin® (bexarotene), which is a RXR agonist with RAR agonist activity as well, was approved by the U.S. Food and Drug Administration for the treatment, both oral and topical, of cutaneous manifestations of cutaneous T-cell lymphoma in patients who are refractory to at least one prior systemic therapy. Further, recent clinical studies that were conducted using Targretin® (bexarotene) suggest that there is potential for RXR agonists in the treatment of non-small cell lung cancer (NSCLC). Encouraging results were obtained with Targretin® in several Phase II studies in NSCLC. However, the pivotal Phase III clinical study did not show increased survival. Therefore, there is a need for new technologies that increase the efficacy of RXR agonists when used to treat solid tumors such as NSCLC.